Rotary engine

ABSTRACT

Disclosed are apparatus for a two cylinder rotary internal combustion engine comprising a stationary cylinder block with a pair of inwardly facing horizontally opposed pistons operating within. Each piston is maintained in fixed relationship to the other by means of a common connecting rod. A cam roller assembly is included at each outer extremity of the opposed pistons for transmitting reciprocating motion to an eccentric cam raceway provided within an outer rotating frame assembly which is rotably mounted with respect to the stationary cylinder block. An output drive shaft is connected to the rotating frame. Tubular cylindrical intake and exhaust valves communicate with each cylinder, with a geneva drive mechanism provided for imparting stepwise counter-rotational motion to said valves for admitting combustible mixture and exhausting combustion gasses at proper intervals. In a preferred embodiment, a four cylinder rotary engine is illustrated comprising two pairs of horizontally opposed piston with two eccentric cam raceways arranged for mechanically balanced operation in a four cycle engine having two power strokes per revolution.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to rotary internal combustion engines andassociated valve apparatus for inducting combustible mixture andeducting exhaust gasses. More specifically, the present inventionrelates to a rotary cam internal combustion engine wherein reciprocatingmotion of horizontally opposed pistons is transformed into rotary outputmotion. Tubular rotary valves are employed for communication ofcombustible mixture to the cylinder bores and for extraction of exhaustgasses at appropriate times in the operational cycle of the engine.

2. Description of Prior Art

A number of rotary type internal combustion engines have previously beenproposed with numerous objectives and advantages attibutable to each.However, of paramount importance today in the face of dwindlinghydrocarbon fuel resources, is the search for a more fuel efficientinternal combustion engine. In addition, improved engines which reduceor minimize pollutants discharged to the environment are highlydesirable.

In response to these and other considerations, several rotary engineshave been divised. For example, U.S. Pat. No. 3,964,450 to Lockshawdiscloses a rotary cam type internal combustion engine comprising astationary cylinder block and a rotatable casing. Reciprocating pistonsare connected to a cam slot machined into the rotatable casing by meansof a connecting rod having a cam follower secured to the outer end ofthe rod. The main drive shaft is attached to the rotatable casing andincorporates fuel intake and exhaust passages. A portion of the maindrive shaft passes through the center of the stationary block andincludes intake and exhaust ports which communicate in timed sequencewith a single port opening in each of a plurality of radially orientedcylinder bores. In U.S. Pat. No. 2,894,496 to Townsend, a rotaryinternal combustion engine comprises a stationary outer cam apparatus, arotary cylinder block assembly, and a stationary shaft which passesthrough the center of the cylinder block. The stationary shaft serves asan inlet and exhaust manifold for radially oriented cylinders, as wellas a journal for the rotating block. Individual pistons within eachradial cylinder include a cam follower means for imparting motion to thepiston as the stationary cam surface is traversed. U.S. Pat. No.4,038,953, also issued to Townsend, discloses a similar rotating blockand stationary cam engine. However, improved means for accomplishingintake and exhaust functions are disclosed.

Although a number of rotary type combustion engines have been proposed,implementation of the concepts involved have been largely unsuccessfuldue to various factors such as complex mechanical arrangements, andexposure of rotating elements to the high temperatures of the exhaustgasses. For example, the engine disclosed in the Lockshaw patentrequires a cam slot which restrains a cam follower in two directions toprovide accurate positioning of the piston throughout the operationalcycle. In both the Lockshaw and Townsend patents, rotating seals forintake and exhaust gasses are required due to clearances which must beprovided between rotating and stationary components. Maintainingeffective sealing of hot exhaust gasses for an acceptable period of timein these designs presents a major problem. Further, in the rotatingblock, stationary cam disclosures, the lack of positive means forstroking a piston through the intake cycle precludes practicalapplication of this apparatus for a normally aspirated four cycleengine.

SUMMARY OF THE INVENTION

Accordingly, there is a need for a practical and more efficient designof a rotary internal combustion engine. It is therefore a principleobject of the present invention to provide such an improved rotaryengine.

Another object of the present invention is to provide a rotary internalcombustion engine having a simple and rugged mechanism for positivepositioning of pistons throughout the operational cycle.

Yet another object of the present invention is to provide a rotaryinternal combustion engine having cam surfaces and cam followers whichare subjected to compressive loadings only.

A further object of the present invention is to provide an improvedrotary internal combustion engine having inlet and exhaust provisionswhich offer minimum resistance to flow and which eliminate the need forrotating seals between stationary and rotatable engine components.

Still another object of the present invention is to provide a simple andrugged rotary valve apparatus capable of withstanding peak combustionpressures and temperatures with minimum leakage.

Another object of the present invention is to provide a novel rotaryvalve actuation apparatus which requires minimum power drain and permitsfull opening of inlet and exhaust valves for a longer period of timewith minimum overlap during transition between intake and exhauststrokes.

Yet another object of the present invention is to provide a novel rotaryvalve apparatus which is capable of serving a pair of cylinders with asingle valve port opening in the cylindrical rotary valve.

The above and other objects of the present invention will becomeapparent from the drawings, the description provided herein, and theappended claims.

The rotary internal combustion engine of the present invention includesa stationary cylinder block having a pair of horizontally opposedcylinder bores. A pair of opposed, inwardly facing pistons are mountedat opposite ends of a common connecting rod which communicates through acentral dividing wall between the two cylinder bores. A cam follower isprovided within the skirt portion of each piston for contact with aneccentric cam surface located within an outer rotating frame assembly.As the interconnected pistons reciprocate within the cylinder block,combustion forces are transmitted to the eccentric cam surface impartingrotational motion to the outer rotating frame. A drive shaft isconnected to the outer rotating frame providing means for transmissionof power. The outer rotating frame assembly is supported for rotationabout the stationary cylinder block by means of bearings located betweenthe cylinder block and a pair of annular flanges provided on therotating frame assembly. A cylindrical housing with circular top andbottom portions completely encloses the stationary block and rotatingframe assembly.

In the illustrated embodiment of the present invention, a pair ofcounter-rotating tubular cylindrical valves are provided for admittingcombustible mixture and exhausting the products of combustion. Cylinderinlet and exhaust ports, adjacent to the common dividing wall betweenthe two cylinder bores in the stationary cylinder block are provided foreach horizontal cylinder. Vertical valve bores for receiving the tubularcylindrical inlet and exhaust valves partially intersect each cylinderinlet and exhaust port, thus providing passageways for communicatingcombustible mixture to the cylinders and exhausting products ofcombustion therefrom. Each cylindrical valve includes an arctuate valveport opening such that, as the valve is rotated, the arctuate valve portopening may align with a cylinder port, thereby permitting entrance orexit of gasses. Openings are included in the engine housing which alignwith the interior portion of the tubular cylindrical valves. Combustiblemixture from any conventional source such as a carburetor, may thus becommunicated to the inlet valve, and exhaust gasses may be withdrawnfrom the engine by the usual piping means.

The tubular cylindrical inlet and exhaust valves each include alongitudinal valve shaft extension which protrudes through a valve shaftbore in the cylinder block. The valve shaft extensions engage valveactuation means which provide timed rotation of the cylindrical valvesat appropriate moments in the operational cycle of the engine.

In an illustrated embodiment, valve actuation is provided by means of ageneva mechanism, the driver element of which is attached to the enginedrive shaft. A geneva driven element is affixed to one valve shaftextension, which also includes a first spur gear mounted thereon. Thesecond valve shaft extension has a second spur gear mounted thereon forengagement with said first spur gear. Through said geneva mechanism andsaid first and second spur gears, counter rotating cylindrical valvesmay be actuated in timed relationship to the degree of rotation of thedrive shaft, by which the geneva drive mechanism is operated. In analternative embodiment, the geneva drive mechanism may be replaced by adrive gear attached to the output shaft of the engine which engages adriven gear on one of the valve shaft extensions. First and second spurgears are also provided on each valve shaft extension as previouslydescribed. The pitch diameters of the drive gear and driven gear are ina ratio of 1:2 to provide the proper degree of rotation of thecylindrical valves with respect to the degree of rotation of the enginedrive shaft.

In a preferred form, the present invention comprises a stationarycylinder block having two adjacent pairs of horizontally opposedcylinder bores with parallel centerlines. First and second pairs ofinwardly facing horizontally opposed pistons, including cam followers,are employed in conjunction with two adjacent eccentric cam surfaceslocated within the outer rotating frame assembly. Cam surfaces are inangular alignment which enables construction of a four cycle internalcombustion engine having a balanced two power strokes per revolution ofthe outer rotating frame assembly. Valving for the second pair ofcylinders is provided by extending each tubular cylindrical valve asufficient distance allowing incorporation of a second valve portopening which aligns with cylinder inlet and exhaust ports provided forthe second pair of cylinders. The second valve port included in eachcylindrical valve may be positioned at an appropriate angular offsetwith respect to the first opening to accomodate a firing order for thesecond pair of cylinders which is 360° out of phase with that of thefirst pair of cylinders.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional plan view of a two cylinder rotary internalcombustion engine according to the present invention;

FIG. 2 is a side elevational view of the engine, partially in section,taken generally along the line 2--2 of FIG. 1;

FIG. 3 is a cross sectional side elevation taken generally along line3--3 of FIG. 2, illustrating a third angle cross sectional view of theapparatus of the present invention;

FIG. 4 is a plan view of rotary valve actuation apparatus, partially insection, taken generally along line 4--4 of FIG. 3;

FIG. 5 is a side elevational view, partially in section, of a fourcylinder rotary internal combustion engine according to the presentinvention;

FIG. 6 is a partial side elevational view, in section, of alternativerotary valve actuation apparatus;

FIG. 7 is a plan view of the apparatus of FIG. 6 taken generally alongline 7--7; and

FIGS. 8A through 8J are a series of partial cross sectional plan viewsof rotary valve apparatus according to the present invention, wherein afour cycle valve sequence of a four cylinder rotary internal combustionengine is illustrated.

DESCRIPTION OF PREFERRED EMBODIMENTS

Reference is now made to the drawings for a detailed description of therotary internal combustion engine according to the present invention.Referring to FIG. 1, the engine shown generally at 10 comprises a pairof horizontally opposed pistons 12a and 12b interconnected by a commonconnecting rod 14. Pistons 12a and 12b are free to reciprocate withincolinear cylindrical bores 16a and 16b, respectively, machined withincylinder block 18. A common dividing wall 20 separates said cylinderbores 16a and 16b to form combustion chambers 22a and 22b for pistons12a and 12b, respectively. A cylindrical bushing and seal assembly 24 isprovided within dividing wall 20 to accommodate passage of connectingrod 14 through said dividing wall. Inlet ports 26a and 26b are providedfor communication of combustible mixture into combustion chambers 22aand 22b, respectively, at the proper moment in the operational cycle ofthe engine. As will be described further below, combustible mixture isadmitted into a combustion chamber via said inlet ports 26a and 26b uponalignment of cylindrical valve port 30 with either of said cylinderintake ports. Likewise, combustion chamber exhaust ports 28a and 28b areprovided for combustion chambers 22a and 22b, respectively. Exhaustgasses are extracted from a combustion chamber 22a or 22b upon thealignment of cylindrical exhaust valve port 32 with either cylinderexhaust port 28a or 28b. Cam followers 34a and 34b are mounted withinthe lower skirt portion of pistons 12a and 12b by means of cylindricalpins 36a and 36b, respectively. Free rotation of cam followers 34a and34b is assured by bearings 38a and 38b provided said cam followers andcylindrical pins 36a and 36b. Cam followers 34a and 34b maintaincontinuous contact with an eccentric cam surface 40 located within anouter rotating ring assembly, shown generally as 42. The outer rotatingring assembly 42 is free to rotate about cylinder block 18. As moreclearly depicted in FIG. 2, the outer rotating ring assembly 42comprises a cylindrical outer ring 48, a pair of annular flanges 46a and46b attached to either extremity of the outer ring 48, and an annularcam ring 50 located midway between said annular flanges. Trunionbearings 44a and 44b are provided on the inner diameter of the annularflanges 46a and 46b to provide free rotation of the rotating ringassembly 42 with respect to cylinder block 18.

Referring again to FIG. 1, the basic operation of the rotary internalcombustion engine of the present invention may be explained by notingfirst that the center of rotation of the outer rotating ring assembly 42is a point x detailed therein. It should also be noted that the centerof the generally circular eccentric cam surface 40 is a point y locateda distance e from point x along the centerline of connecting rod 14. Inthe position illustrated, piston 12a is at its bottom dead center, whilepiston 12b is at its top dead center of travel. For reference purposes,this position may be designated as zero degrees of rotation of therotating ring assembly 42. As the outer rotating ring assembly rotatesabout point x, linear displacement is imparted to the piston assembly bymeans of cam followers 34a and 34b which maintain contact with theeccentric inner raceway 40. At 180° of rotation of the outer ringassembly 42 from the position shown in FIG. 1, the maximum lineardisplacement of interconnected pistons 12a and 12b is attained. At thatpoint piston 12a is at its top dead center of travel, while piston 12bis at its bottom dead center of travel. It will be understood by oneskilled in the art that in this position, the eccentric inner racewayhas also rotated 180° resulting in the linear movement of theinterconnected pistons a distance equal to twice the distance e. As theouter rotating ring assembly 42 continues rotation beyond 180°, theinterconnected pistons reverse direction of travel and approach theposition illustrated in FIG. 1 as 360° of rotation, or one completerevolution of the outer rotating ring 42, is completed. The total pistontravel in one direction, or piston stroke, is thus equivalent to twicethe distance e between points x and y as shown in FIG. 1. The camprofile of the eccentric raceway 40 may be varied to control thecharacteristic of the linear motion imparted to interconnected pistons12a and 12b. For example, surface 40 may represent a constantacceleration cam profile to eliminate non-uniform linear accelerationpeaks or alternatively, surface 40 may represent a cam profile whichproduces a desired amount of piston displacement for a given degree ofrotation of the outer rotating ring assembly 42. By comparison, aconventional crank type reciprocating piston engine produces a majorityof piston travel over a relatively small portion of rotation of thecrank, and this relationship between crank rotation and pistondisplacement may not be varied.

Referring again to FIG. 2, the outer rotating ring assembly 42 rotatesabout cylinder block 18, and is held in position with respect thereto bymeans of upper and lower trunion bearings 44a and 44b respectively, eachof which comprises a circular inner race 52, a circular outer race 56,and a plurality of spherical balls 54 dispersed between said inner andouter races. Power output of the engine is transmitted through outputshaft 58 which is connected to the outer rotating ring assembly 42 atthe center of rotation of said ring by means of a cylindrical bracket60. The engine block 18 and rotating ring assembly 42 are completelyenclosed by a cylindrical housing 62 and a circular base plate 64. Anopening 68 is provided within base plate 64 for extension of outputshaft 58 therethrough with a bearing 70 provided between the rotatingshaft 58 and the stationary base plate 64. As detailed in FIG. 3, anopening 72 is provided in housing 62 for communication of combustiblemixture to a cylindrical inlet valve 31. Likewise, an opening 74 is alsoprovided in housing 62 for extraction of exhaust gasses from cylindricalexhaust valve 33.

The cylindrical inlet valve 31 is received within a cylindrical bore 80in cylinder block 18 as shown in FIG. 3. An inlet valve shaft extension88 extends from the base portion of inlet valve 31 through a reducedbore 82 which is concentric with valve bore 80. Likewise, exhaust valve33 is received in an exhaust valve bore 84 also provided in cylinderblock 18. An exhaust valve shaft extension 90 extends from the baseportion of exhaust valve 33 through a reduced bore 86 which isconcentric with exhaust valve bore 84. Inlet and exhaust valve shaftextensions, 88 and 90 respectively, extend through respective reducedbores 82 and 86 in cylinder block 18 to engage rotary valve apparatuscomprising first and second gears, 100a and 100b respectively, whichmesh together to provide a fixed counter-rotational relationship betweensaid inlet and exhaust valves. In the illustrated embodiment of FIG. 3,timed valve actuation is accomplished by means of a geneva drivemechanism, the driven element 98 of said mechanism being attached tovalve shaft extension 88. The geneva driving element, comprising pins92a and 92b attached to cylindrical bracket 60, and a positioner element94 attached to output shaft 58 by means of key 96, rotates in directrelationship to degree of engine rotation. Actuation of the drivenelement 98 by driving pins 92a and 92b results in valve actuation whichis proportional to degree of rotation of the engine. As more clearlydepicted in FIG. 4, the geneva driven element 98 comprises fouridentical slots as typified by slot 102, equally spaced at 90° intervalsabout the periphery of said geneva driven element 98. Each of said slotsalternately engage pins 92a and 92b of the geneva driving elementattached to the rotating bracket 60 and output drive shaft 58. As istypical for this type of driving arrangement, the uniform rotationalmovement of the geneva driving element is transformed into a stepwiserotational movement of the geneva driven element 98. In the illustrationof FIG. 4, four discrete steps of valve rotation occur during onecomplete revolution of the driven element 98, and this in turn requirestwo complete revolutions of the engine output shaft 58 and the genevadriving elements, pins 92a and 92b. With the geneva driven element 98attached to inlet valve shaft extension 88, the rotary motion impartedto intake valve 31 is also transmitted to exhaust valve 33 by means ofspur gears 100a and 100b also attached to said valve shaft extensions 88and 90. The stepwise rotation of intake and exhaust valves 31 and 33respectively, provides optimum valve positioning for the intake,compression, power and exhaust strokes of a four cycle internalcombustion engine. With this arrangement, valve openings may bemaintained for a longer period of time with less restriction to flow ofgasses, and a lesser degree of valve overlap such as is normallyrequired in internal combustion engines utilizing conventional poppettype valve means.

Referring to FIGS. 6 and 7, an alternative embodiment of valve actuationapparatus comprises a first gear 104 attached to drive shaft 58 rotatingin direct relation to degree of engine rotation, and a second gear 106which meshes with said first gear. Said second gear 106 is attached tointake valve shaft extension 88, imparting rotary motion thereto. Thepitch diameters of said first and second gears are fixed to provide thecorrect ratio of valve rotation with respect to engine rotation. Aspreviously described, spur gears 100a and 100b, mounted on intake valveshaft extension 88 and exhaust valve shaft extension 90, respectively,mesh together providing coordinated counter-rotational motion betweensaid intake valve 31 and exhaust valve 33. Thus, rotary motion impartedto intake valve 31 by means of said first gear 104 and said second gear106 results in corresponding counter-rotational movement of exhaustvalve 33.

With reference to FIG. 5, a four cylinder, four cycle rotary internalcombustion engine according to the present invention is illustrated. Theengine comprises a stationary cylinder block 108 having first and secondpairs of inwardly facing horizontally opposed pistons interconnected bycommon connecting rods 110 and 112 respectively. An outer rotating frameassembly 114 includes first and second eccentric cam surfaces 116 and118, each of which operates in conjunction with one pair of horizontallyopposed cylinders. Eccentric cam surfaces 116 and 118 may be positionedin phase with each other such that both pairs of horizontally opposedpistons move in unison. Tubular cylindrical inlet and exhaust valves,120 and 122 respectively, are provided within cylinder block 108 foradmission of combustible mixture and exhaust of products of combustion.Cylindrical valves 120 and 122 are rotably operated by appropriate valveactuation means as previously described, and each includes first andsecond valve port openings for alignment with matching cylinder intakeand exhaust ports at the appropriate moments in the operational cycle ofthe engine. The outer rotating frame assembly 114 freely rotates aboutcylinder block 108 by means of upper and lower bearings 130 and 128respectively. A cylindrical bracket 124 is attached to the rotatingframe assembly 114 for transmission of the rotary motion to output shaft126 attached thereto. A stationary plate 132 and cover 134 completelyenclose the engine. It will be understood by those skilled in the artthat the above described four cylinder rotary internal combustion enginerepresents an extension of the basic concept of the present inventionillustrated in FIGS. 1-3. Specifically, it is obvious that the apparatusof FIG. 5 comprises the integration of a pair of two cylinder rotaryinternal combustion engines of the present invention into a singleoperating unit, retaining only those components necessary, andeliminating all others. For example, the addition of a second pair ofhorizontally opposed cylinders is accomplished as shown without furthermodification or complication of the valve actuation apparatus of FIGS. 3and 4. The result illustrated in FIG. 5 is a compact four cylinderrotary internal combustion engine having a minimum of additional movingparts. Further it can be seen that additional pairs of cylinders couldbe added without difficulty.

Detailed rotary valve operation in an engine according to the presentinvention is illustrated in FIG. 8. FIGS. 8A through 8E illustraterotary valve function in a two cylinder internal combustion engine suchas that previously described in connection with FIGS. 1-3. Inparticular, the valve sequence illustrated is that associated with afour cycle engine, with the respective power, exhaust, intake, andcompression cycle being illustrated for pistons 12a and 12b in FIGS.8A-8E. In FIG. 8A, piston 12a is approaching its top dead centerposition, completing a compression stroke. Inlet port 26a and exhaustport 28a are sealed off, or closed, at this point by the cylindricalwalls of intake valve 31 and exhaust valve 33 respectively. As piston12a completes its compression stroke, ignition is accomplished byconventional means and the power stroke for piston 12a is initiated. Atthis point, piston 12b has completed its power stroke and is initiatingits exhaust stroke. Intake valve 31 is now rotated 90° clockwise whileexhaust valve 33 is rotated 90° counter-clockwise. These valve positionsmay be clearly understood with reference to FIG. 8B. It will be notedhere that upon rotation of exhaust valve 33 at the commencement ofpiston 12b exhaust stroke, exhaust valve port 32 becomes aligned withcylinder port 28b permitting escape of exhaust gasses. With piston 12bnearing the completion of its exhaust stroke and piston 12a (not shown)completing its power stroke, intake valve 31 is now rotated 90°clockwise, while exhaust valve 33 is rotated 90° counter-clockwise, tothe positions illustrated in FIG. 8C. In this position, inlet valve port30 is aligned with cylinder port 26b permitting entrance of combustiblemixture for the intake stroke of piston 12b. With the rotation ofexhaust valve 33, cylinder exhaust port 28b has been closed off by thecylinder wall of valve 33 while exhaust valve port 32 is now alignedwith cylinder port 28a permitting exhaustion of gasses during theexhaust stroke of piston 12a. In FIG. 8C piston 12a is nearingcompletion of its exhaust stroke while piston 12 b (not shown) isnearing completion of its intake stroke. At this point, intake andexhaust valves 31 and 33 again rotate 90° in their respective directionsto the positions shown in FIG. 8D. In this position, it is obvious thatcylinder exhaust port 28a has been closed off while cylinder inlet port26a is now aligned with inlet valve port 30 permitting entrance ofcombustible mixture during the intake stroke of piston 12a. It shouldalso be noted that cylinder ports 26b and 28b are closed off the bycylindrical walls of inlet valve 31 and exhaust valve 33, respectively,for the compression stroke of piston 12b. As piston 12b is nearing thecompletion of its compression stroke as shown in FIG. 8D, inlet valve 31and exhaust valve 33 again rotate in their respective directions withthe result that both cylinder ports 26a and 28a are closed off inpreparation for the compression stroke of piston 12a. Cylinder ports 26band 28b also remain closed at this point for the power stroke of piston12b. These valve positions are shown more clearly in FIG. 8E. In thisposition, inlet valve 31 and exhaust valve 33 have completed one fullrevolution, during which time each of pistons 12a and 12b have undergoneone complete series of operational strokes which are typicallyassociated with a four cycle engine, power, exhaust, intake andcompression.

FIGS. 8F-8J represent a similar sequence of valve operation for a secondset of horizontally opposed pistons 144a and 144b which may be locatedadjacent to pistons 12a and 12b in an arrangement similar to thatillustrated in FIG. 5. In this instance, tubular inlet valve 31 andexhaust valve 33 are extended to incorporate an additional set of valveports, such as inlet valve port 142 and exhaust valve port 146 as shownin FIG. 8F. An additional set of cylinder intake ports 140a and 140b,and an additional set of cylinder exhaust ports 144a and 144b areprovided for said second set of horizontally opposed pistons 136a and136b. As detailed in FIG. 8F, piston 136a is completing its exhauststroke with exhaust valve port 146 aligned with cylinder exhaust port144a. Likewise, piston 144b (not shown) is nearing completion of itsintake stroke, with intake valve port 142 aligned with cylinder intakeport 140b. In a four cylinder rotary internal combustion engine such asthat illustrated in FIG. 5, the valve and piston positions of FIG. 8Ffor the second set of horizontally opposed pistons 136a and 136b may berelated to the valve and piston positions of the first pair ofhorizontally opposed pistons 12a and 12b as illustrated in FIG. 8A. Forexample, while piston 12a of FIG. 8A is nearing completion of itscompression stroke, piston 136a of FIG. 8F is nearing completion of itsexhaust stroke. In this manner the firing order of a four cylinder,internal combustion engine as illustrated in FIGS. 8A-8J would followthe order of piston 12a, piston 136b, piston 136a, and finally, piston12b. However, it will be understood by one skilled in the art, thatnumerous phase relationships between a first pair of horizontallyopposed pistons and a second pair of horizontally opposed pistons may beaccomodated by adjusting the phased relationship of eccentric camsurfaces 116 and 118 of FIG. 5, and by providing corresponding angularadjustments in the relative positioning of inlet valve ports 30 and 142,and exhaust valve ports 32 and 146 detailed in FIG. 8.

Although not shown, it will be appreciated that spark plug or fuelinjection means can be provided.

From the above description, it is apparent that numerous modificationsmay be made in the apparatus of the present invention without departingfrom the scope thereof. Accordingly, it is intended that the inventionbe limited only by the appended claims.

I claim:
 1. A rotary internal combustion engine apparatus comprising:(a)a stationary cylinder block having at least one pair of opposed cylinderbores; (b) at least one pair of opposed piston means for reciprocatingoperation within said one pair of opposed cylinder bores; (c) a pistonconnecting means comprising a rod connecting at least one pair ofopposed piston means together; (d) a dividing wall between said pair ofcylinder bores, having a reduced bore concentric with said cylinderbores for communication of said piston connecting means therethrough;(e) inlet and exhaust means communicating with each cylinder bore andcomprising:(i) a cylinder inlet port and a cylinder exhaust portcommunicating with each cylinder bore, generally positioned adjacent toopposite ends of said dividing wall; (ii) first and second valve boresoriented generally transversely to said cylinder bores and communicatingwith said cylinder inlet and exhaust ports, respectively, and alignedwith said dividing wall; (iii) first and second valve shaft bores,concentric with said first and second valve bores, passing through saidstationary cylinder block; (iv) a first rotatable valve means containedwithin said first valve bore for timed admission of combustible fuelmixture; (v) a second rotatable valve means contained within said secondvalve bore for timed extraction of exhaust gases; (vi) rotatable valveactuation means for timed rotation of said first and second rotatablevalve means; and (vii) opposing cylinder inlet and exhaust portsintersecting respective ones of said cylindrical valve bores anddisplaced from one another; (f) a cam follower means at each extremityof said one pair of opposed piston means; (g) at least one rotatableeccentric cam means coacting with said cam follower means; (h) arotatable frame means secured about said cam means; (i) an output drivemeans connected to said rotatable frame means; and (j) a housing meansfor enclosing said rotatable frame means and stationary cylinder block.2. The apparatus of claim 1 wherein said one pair of opposed pistonmeans comprise two cylindrical pistons affixed to opposite ends of saidpiston connecting means, the combustion side of each piston facinginwardly toward the other.
 3. The apparatus of claim 1 wherein saidpiston connecting means comprises an elongated cylindrical rod.
 4. Theapparatus of claim 1 wherein said rotatable valve actuation meanscomprise:(a) a geneva drive mechanism, including a geneva driven elementattached to said rotatable frame means and a geneva driven elementattached to said solid cylindrical portion of said first rotatable valvemeans; (b) a first gear attached to said solid cylindrical portion ofsaid first rotatable valve means; and (c) a second gear attached to saidsolid cylindrical portion of said second rotatable valve means, andmeshing with said first gear.
 5. The apparatus of claim 1 wherein saidrotatable valve actuation means comprise:(a) a driver gear attached tosaid rotatable frame means; (b) a driven gear attached to said solidcylindrical portion of said first rotatable valve means, and meshingwith said driver gear; (c) a first gear attached to said solid portionof said first rotatable valve means; and (d) a second gear attached tosaid solid cylindrical portion of said second rotatable valve means, andmeshing with said first gear.
 6. The apparatus of claim 1 wherein saidcam follower means comprise:(a) a cam roller support structure; (b) acam roller; and (c) a cam roller pin for attaching said cam roller tosaid cam roller support structure.
 7. The apparatus of claim 1 whereinsaid output drive means comprise a cylindrical drive shaft.
 8. Theapparatus of claim 1 wherein said housing means comprise:(a) acylindrical shroud surrounding said rotatable frame means; (b) an upperportion covering said rotatable frame means and stationary block, withopenings for communication with said inlet and exhaust means; and (c) alower portion covering said rotatable frame means and stationary block,with an opening for extension of said output drive means.
 9. Theapparatus of claim 1 wherein said rotary internal combustion enginecomprises a four cycle engine having two cylinders, with one powerstroke occurring for each revolution of said rotatable frame means. 10.The apparatus of claim 1 wherein said rotatable frame means comprise:(a)a generally annular rotatable cam ring; (b) an outer cylindrical portionattached to said cam ring; (c) a first annular flange attached to afirst end of said outer cylindrical portion; (d) a second annular flangeattached to a second end of said outer cylindrical portion; and (e)bearing means attached to the inner diameter of said first and secondannular flanges for engagement with said stationary cylindrical block tofacilitate rotation of said rotatable frame with respect to saidstationary cylinder block.
 11. The apparatus of claim 10 wherein saidbearing means comprise:(a) a circular outer race on each of said firstand second annular flanges; (b) a circular inner race provided on saidstationary cylinder block opposite each said circular outer race; and(c) a plurality of spherical balls dispersed between said inner andouter races.
 12. The apparatus of claim 1 wherein said rotatable cammeans comprise a generally annular rotatable cam ring with a generallycircular inner surface eccentrically positioned with respect to thecenter of rotation of said cam ring.
 13. The apparatus of claim 12wherein said generally circular inner surface comprises a constantacceleration cam profile.
 14. The apparatus of claim 12 wherein saidgenerally circular inner surface comprises a cam profile wherein thedistance between contact points of said cam follower means with saidsurface is a constant, irrespective of degree of rotation of saidrotatable cam means.
 15. The apparatus of claim 1 wherein each of saidfirst and second rotatable valve means comprise:(a) a hollow cylindricalportion for insertion within said first and second valve bores; (b) afirst valve port opening in the wall of said hollow cylindrical portionfor communication with said cylinder inlet and exhaust ports; and (c) asolid cylindrical portion of lesser diameter for passage through saidfirst and second reduced bores and engagement with said rotatable valveactuation means.
 16. The apparatus of claim 15 wherein each of saidfirst and second rotatable valve means further comprise a second valveport opening in the wall of said hollow cylindrical portion forcommunication with said cylinder inlet and exhaust ports associated witha second pair of opposed cylinder bores.
 17. The apparatus of claim 16wherein said second valve port opening is located 180 degrees oppositeto said first valve port opening.
 18. The apparatus of claim 1 furthercomprising:(a) a second pair of opposed cylinder bores; (b) a seconddividing wall between said second pair of opposed cylinder bores; (c) asecond pair of opposed piston means; (d) a second piston connectingmeans; (e) a second cam follower means at each extremity of said secondpair of opposed piston means; and (f) a second rotatable cam meanscontained within said rotatable frame means.
 19. The apparatus of claim18 wherein said second pair of opposed cylinder bores are parallel tosaid one pair of opposed cylinder bores, and vertically adjacentthereto.
 20. The apparatus of claim 18 wherein said second rotatable cammeans is positioned 180 degrees out of phase with respect to said onerotatable cam means.
 21. The apparatus of claim 18 wherein said rotaryinternal combustion engine comprises a four cycle engine having fourcylinders, with two power strokes occurring for each revolution of saidrotatable frame means.